Film deposition method and apparatus

ABSTRACT

In the film deposition method of the present invention, an organometallic fluid, which has an organic metal such as a copper diketonate as its main component, and which precipitates film deposition material through a pyrolytic decomposed reaction, is first prepared; and the organometallic fluid is then applied onto a semiconductor wafer at a certain temperature within the non-reactive range of the organic metal. Afterwards, the wafer is heated to a predetermined temperature, the organic metal within the organometallic fluid that is applied onto the wafer is pyrolytically decomposed, and film is formed on the wafer. With this method, since application is performed at a temperature within the non-reactive range of the organic metal, deposition of the film does not occur, allowing uniform and homogenous application to be performed. Also, since pyrolytic decomposition is performed separately in a later process, a stable reaction may be assured, so that a film of uniform thickness and quality may be deposited.

TECHNICAL FIELD

The present invention relates to fabrication processing techniques ofsemiconductor devices and related devices. In particular, it relates totechniques for performing film deposition using fluids that have anorganic metal as the main component (organometallic fluids).

BACKGROUND ART

In recent years, as improvements in the integration and miniaturizationof the semiconductor device progresses, there has been a steady shiftfrom the present sub-half-micron range to the sub-quarter-micron range.In this quest to develop the next generation of semiconductor devices,film deposition techniques are exceedingly important.

In response to demands for improvements in integration and furtherminiaturization, switching from aluminum-based materials to copper-basedmaterials being used as interconnective material is under consideration.Presently, metalorganic chemical vapor deposition (MOCVD), which isperformed by vaporizing an organic metal, such as (hfac)Cu⁺¹(tmvs),which is usually fluid at room temperature and under normal pressure,introducing it to the process chamber, and depositing a film by causinga pyrolytic decomposition reaction to occur on the wafer being held insaid process chamber, is put to use.

Such conventional MOCVD processes thus provide superb step coverage andare extremely effective in the fabrication of very thin films. However,with these MOCVD processes, at times when it is necessary to guarantee asufficient layer thickness, for example during the step of filling incontact holes, problems such as the lack of efficiency develop. It takestime to fill in the hole completely since there is a limit to thethickness of the layer which can be accumulated during a certain lengthof time due to the low amounts of the organic metal itself existing inthe process chamber, resulting from the low pressure in the processchamber. There is an additional danger of the vaporized organic metalreacting inside the supply pipeline and clogging the pipes.

The present invention takes the above information into consideration andaims to provide a film deposition process and apparatus, which useorganometallic fluids, wherewith highly effective film deposition can beperformed without causing blockage in the supply pipeline.

DISCLOSURE OF THE INVENTION

In order to fulfill the objective mentioned above, the inventorsconsidered many variables. As a result, they found that the pyrolyticdecomposition of organometallic fluid occurs by heating it even if itdoes not vaporize thus resulting in film formation. From this, theinventors considered methods of applying organometallic fluid whileheating the wafer; however, with this method, since pyrolyticdecomposition successively occurs as it is applied, they came to theconclusion that it is difficult to perform uniform film depositionthroughout the wafer. The present invention was first formulated basedon these findings.

Namely, the present invention is characterized by a film depositionprocess comprising a first step of preparing a fluid that has organicmetal as a main component, which deposits a film deposition materialusing pyrolytic decomposition; a second step of applying theorganometallic fluid onto a to-be-processed body at a temperature withinthe non-reactive domain of said organic metal; and afterwards, a thirdstep of heating the to-be-processed body to a predetermined temperature,and causing pyrolytic decomposition of said organic metal throughout theorganometallic fluid that is applied onto the to-be-processed body toform a film on the to-be-processed body.

With this method, since application is performed at a temperature withinthe non-reactive domain of said organic metal, a film depositionmaterial is not deposited. Therefore, the application can be performeduniformly and homogenously. In addition, pyrolytic decomposition will beperformed by itself after this so that a stable reaction may beguaranteed and a film with uniform thickness and quality may be formed.

It is noted here that the organometallic fluid may comprise solely anorganic metal, or it may comprise a mixture of an organic metal and asolvent. It is also noted that in this specification, ‘mixed fluids’ mayrefer to cases where the organic metal is completely dissolved or it mayrefer to cases where part of it is suspended. Furthermore, ‘application’may refer to cases where the to-be-processed body is immersed into theorganometallic fluid, or it may refer to cases such as where theorganometallic fluid is atomized and then applied.

As for the organic metal, any suitable copper diketonate such as(hfac)Cu⁺¹(tmvs) or (hfac)Cu⁺¹(teovs) may be used for copper filmdeposition, and any suitable aliphatic saturated hydrocarbon such asheptadecane, pentadecane, hexadecane, or octadecane may be used as thesolvent thereof.

It is preferable that the film deposition apparatus used to execute thefilm deposition method above comprise a supply means, which supplies anorganometallic fluid that has organic metal as a main component, fordepositing a film deposition material using pyrolytic decomposition; anapplication means, which applies an organometallic fluid that issupplied from the supply means onto a to-be-processed body; and aheating means, which heats the to-be-processed body to a predeterminedtemperature; wherein said heating means heats the to-be-processed bodyafter the application of organometallic fluid by the application means.

When separate process chambers are provided for the respectiveapplication means and heating means, an appropriate carrying means maybe used to transport the to-be-processed body between the two processchambers.

When both the application means and the heating means are provided in asingle process chamber, a transfer means is provided for transferringthe to-be-processed body from a first area, where application isperformed by the application means, to a second area, where heating isperformed by the heating means.

These and other objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription to those skilled in the art, when taken in conjunction withthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the constitutional formula of (hfac)Cu⁺¹(tmvs);

FIG. 2 is an explanatory diagram that schematically illustrates thefirst embodiment of a film deposition apparatus according to the presentinvention;

FIG. 3 illustrates the reaction equation of the pyrolytic decompositionreaction of (hfac)Cu⁺¹(tmvs);

FIG. 4 is a partial cross-sectional view showing an outline of analternative application device for the film deposition apparatus in FIG.2;

FIG. 5 is a partial cross-sectional view showing an outline of adifferent alternative application device for the film depositionapparatus in FIG. 2;

FIG. 6 is a partial cross-sectional view showing an outline of a meansof stopping the adhesion of film deposition fluid to the beveled portionof the wafer;

FIG. 7 is a partial cross-sectional view showing an outline of adifferent means of stopping the adhesion of film deposition fluid to thebeveled portion of the wafer;

FIG. 8 is a main section oblique perspective view showing an outline ofyet another alternative application device for the film depositiondevice in FIG. 2;

FIG. 9 is a main section oblique perspective view showing an outline ofthe alternative application device in FIG. 8;

FIG. 10 is a cross-sectional view showing an outline of anotheralternative application device for the film deposition device in FIG. 2;

FIG. 11 is a cross-sectional view of an outline of the second embodimentof the film deposition apparatus according to the present invention anda diagram illustrating the state of the application procedure;

FIG. 12 is a cross-sectional view showing the state of the pyrolyticdecomposition procedure for the film deposition apparatus shown in FIG.11; and

FIG. 13 is a schematic cross-sectional view of an alternative secondembodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

In the following, the preferred embodiments according to the presentinvention will be described in detail while referencing the Figures. Itis noted here that throughout all of the drawings, the same orcorresponding parts are labeled with the same respective referencenumerals and repetitive descriptions are omitted. Furthermore, in thefollowing embodiments, the case of using (hfac)Cu⁺¹(tmvs), which is anorganic metal, as the film base material, and forming a thin film ofcopper on the surface of the semiconductor wafer is assumed. Theconstitutional formula of (hfac)Cu⁺¹(tmvs) is shown in FIG. 1, and it isin its fluid state in an environment of normal pressure at roomtemperature. In addition, the viscosity of (hfac)Cu⁺¹(tmvs) is low, andalthough it can be applicable for use as it is in the present inventionto be described below, in the following embodiments, it is mixed with anorganic solvent such as heptadecane to allow for easier handling. In thefollowing, the organometallic fluid containing this (hfac)Cu⁺¹(tmvs) isreferred to as ‘film deposition fluid’.

FIG. 2 illustrates the first embodiment of the film deposition apparatusaccording to the present invention. Film deposition apparatus 10 shownin the figure comprises first process chamber 12, in which is performedprocessing that applies film deposition fluid to the object to beprocessed, that is, the semiconductor wafer W; and second processchamber 14, in which is performed processing that pyrolyticallydecomposes the organic metal, or in other words, the (hfac)Cu⁺¹(tmvs) onwafer W.

First process chamber 12 and second process chamber 14 are connectedthrough transfer chamber 16, which is located between them, and wafer Wcan be transferred between process chambers 12 and 14 using anappropriate carrying means (not shown in the Figure) In the Figure,reference numerals 18 and 20 refer to the slit valves that open andclose the sections between transfer chamber 16 and process chambers 12and 14, respectively.

Turntable 22 is configured inside first process chamber 12 to holdsemiconductor wafer W. Wafer W is mounted horizontally on the uppersurface of this turntable 22, and is held in place with an appropriateholding means such as a vacuum chuck, not shown in the Figures.Turntable 22 shown in the Figure has a diameter that is smaller than thediameter of wafer W, because if the diameter of turntable 22 were largerthan wafer W, not only would film deposition fluid adhere to wafer W,but also to the exposed portions of turntable 22, which can havenegative repercussions for the next wafer W to be processed. Inaddition, turntable 22 is structured to allow it to be turned atrelatively high speeds by a drive motor 24, which is configured externalto first process chamber 12.

In first process chamber 12, application device (application means) 26is further provided for applying film deposition fluid to the surface ofwafer W. Application device 26 comprises supply pipeline 30, whichintroduces film deposition fluid from film deposition fluid supplysystem (supply means) 28 configured external to first process chamber12; and nozzle 32, which extends horizontally from the upper terminal ofthis supply pipeline 30 and has its end facing downward. The maincomponents of supply system 28 are (hfac)Cu⁺¹(tmvs) source 34;heptadecane source 36; and mixing device 38, which mixes the fluids fromsources 34 and 36 to form the film deposition fluid. Supply pipeline 30is configured so that it may be rotationally driven both backwards andforwards by actuator 40, which may be, for example, a drive motor, andbecause of this nozzle 32 is able to swing about the center axis ofsupply pipeline 30. Since the distance from the axis of supply pipeline30 to the end of nozzle 32 is approximately the same as the distancefrom the axis of supply pipeline 30 to the rotational center ofturntable 22, the tip of nozzle 32 is able to pass above the exactcenter of wafer W supported on turntable 22.

Drainpipe 42 is configured adjacent to turntable 22. The upper end ofthe fluid receptor of this drainpipe 42 is positioned so that whennozzle 32 is at its starting position after evacuating from turntable22, it is directly under the end of nozzle 32. Because of this, any filmdeposition fluid that drips from nozzle 32 can be collected through thecollection system (not shown in the Figures) in its pre-reaction state.There is also a ring-shaped, gutter-like member 46 configured around therim of turntable 22. This gutter-like member 46 is used to collect filmdeposition fluid that splashes off wafer W. It is preferable to collectand reuse (hfac)Cu⁺¹(tmvs) since it is a high cost material. Besidesthis type of collection means, which utilizes drain pipe 42 andgutter-like member 46, any number of variations of collection means suchas forming a collection duct in the bottom surface of process chamber 12may also be considered. It is possible to then regenerate(hfac)Cu⁺¹(tmvs) from the collected film deposition fluid. In suchsituations, the organic metal may be utilized more economically, whichcontributes to an overall reduction in base material costs. Moreover,after collecting the film deposition fluid, it is also possible toperform filter ring processing and reusing the film deposition fluid.

Likewise, turntable 48 is configured in second process chamber 14 tohold wafer W in a manner such that it can be rotated. This turntable 48has basically the same mechanism as turntable 22 in first processchamber 12, whereby it is rotated by drive motor 50 and can hold wafer Win place using an applicable means such as a vacuum chuck. However,turntable 48 rotates at a slower speed than turntable 22 in firstprocess chamber 12. In addition, the diameter of turntable 48 is madelarger than the diameter of wafer W. This difference is necessary forcausing a pyrolytic decomposition reaction of the organic metal touniformly occur on the surface of wafer W in second process chamber 12.

Above turntable 48, a plurality of heating lamps 52, which may be forexample halogen lamps, are configured placed behind silica glass plate54. This configuration allows the surface of the wafer W that is lockedonto turntable 48 to be heated. Temperature control is achieved based onthe signals output from temperature gages (not shown in the Figure) suchas a thermoelectric couple attached to turntable 48 or a pyrometerconfigured on the ceiling of process chamber 14, and is performed byregulating device 56, which comprises for example a microcomputer, thatturns on and off, or regulates the amount of power input to heatinglamps 52.

It is noted here that in FIG. 2, reference marker 58 refers to supplysource 58 of a certain inert gas such as nitrogen gas, and is configuredto supply a certain inert gas to first process chamber 12 and secondprocess chamber 14, respectively. On each of the pipelines from inertgas supply source 58 there are configured respective flow regulatingvalves 60 and 62. In addition, reference numbers 64 and 66 refer toexhaust pumps, which are used to evacuate the atmosphere inside processchambers 12 and 14, respectively. These exhaust pumps 64 and 66,together with flow regulating valves 60 and 62, are regulated byregulating device 56 described above. Regulating device 56, in thisfirst embodiment, further regulates drive motors 24 and 50 of turntables22 and 48; swinging actuator 40 of nozzle 32; open/close valves 68, 70,and 72 and mixing device 38 in film deposition fluid supply system 28;and mass flow rate regulating devices 74 and 76.

Next, the procedure will be described for performing copper filmdeposition using film deposition apparatus 10 with the structuredescribed above. It is noted here that, while not specifically stated,the following procedure is automatically performed under the managementby regulating device 56.

To begin with, wafer W is sent into first process chamber 12 and wafer Wis placed at a predetermined position on the upper surface of turntable22 and locked in. At this point, in order to prevent oxidization of thesurface of wafer W or other reactions from happening, it is preferablethat an inert gas such as nitrogen gas be supplied from inert gas supplysource 58 while driving exhaust pump 64, to form an inert gas atmosphereinside of first process chamber 12.

Next, drive motor 24 is activated causing turntable 22 to rotate at apredetermined rotational speed and at the same time the end of nozzle 32is positioned directly above the center of wafer W, film depositionfluid is poured onto the surface of wafer W from film deposition fluidsupply system 28 through supply pipeline 30 and nozzle 32. Sinceturntable 22 is rotating at a relatively high speed, the film depositionfluid poured onto wafer W spreads out towards its rim due to centrifugalforce so that the surface of wafer W may be coated with film depositionfluid. The rotational speed of turntable 22 is set depending onvariables such as the viscosity of the film deposition fluid and theamount supplied. Actuator 40 is then activated and at the same timebegins to swing nozzle 32 at an appropriate frequency and speed to applyfilm deposition fluid across the entire surface of wafer W with uniformthickness and quality.

When the pressure inside first process chamber 12 is set higher thannormal air pressure, coverage is improved by the effects of air pressureforcing it in. In cases where filling-in processing is being performed,openings such as contact holes and trenches formed in the surface ofwafer W can be surely filled in so that the development of problems suchas vacancies can be avoided. Moreover, the temperature inside firstprocess chamber 12 should be the temperature of the organic metal(hfac)Cu⁺¹(tmvs) in its non-reactive range, and preferably normal roomtemperature.

A quantity of the film deposition fluid supplied to wafer W splatter offfrom the edge of wafer W due to the centrifugal force. As a result, thefilm deposition fluid is not able to travel around onto the exposedportion of the underside of wafer W to prevent film from being depositedon the undersurface of the wafer. The formation of film on the undersideof wafer W can have the undesired effect of causing it to beparticlized. In addition, since the gutter-like member 46 is provided inthe first embodiment, the film deposition fluid that has been splatteredcan be collected into the appropriate collection system via gutter-likemember 46 allowing it to be reused.

Once the application procedure has ended, the supply of film depositionfluid is terminated, and while the end of nozzle 32 is returned to itsoriginal position directly over drainpipe 32, the rotation of turntable22 is stopped. There is a possibility that film deposition fluid maydrip from the end of nozzle 32; however, such a film deposition fluidwill be received and collected by fluid receptor 44 of drainpipe 42.

Next, slit valves 18 and 20 are temporarily opened up and using acarrying means (not shown in the Figure) wafer W is moved from firstprocess chamber 12 to second process chamber 14 through transfer chamber16, placed on turntable 48 in a predetermined position, and locked intoplace. The air inside second process chamber 14 has already been madeinto an inert gas atmosphere during the application procedure describedabove, and the pressure inside is set higher than normal air pressure.It is noted here that by also making an inert gas atmosphere insidetransfer chamber 16, it is possible to perform an entire processingseries without exposing wafer W to the outside air, thereby preventingharmful influences such as natural oxidation.

Once wafer W has been placed in the predetermined position, drive motor50 is activated causing turntable 48 to rotate while also activatingheating lamps 52 and regulating them to increase the temperature ofsurface of wafer W to a predetermined temperature, for example between150° C. and 200° C. This causes a pyrolytic decomposition reaction ofthe (hfac)Cu⁺¹(tmvs) contained in the film deposition fluid coating thesurface of wafer W, which yields the precipitation of a copper film onthe surface of wafer W. The pyrolytic decomposition reaction of(hfac)Cu⁺¹(tmvs) is as shown in FIG. 3.

During this reaction, the Cu⁺²(hfac)₂ and tmvs that are formed arereleased out of second process chamber 14 by exhaust pump 66 becausethey change into their respective gas state because of the temperatureinside second process chamber 14 during the pyrolytic decompositionreaction. Also due to the temperature, the organic solvent heptadecaneis evaporated off of wafer W and released without leaving a trace.

As described above, the uniform thickness and quality of the layer offilm deposition fluid throughout the entire surface of wafer W allowsthe copper film being formed to have uniform film thickness and qualityas well. In addition, the fact that turntable 48 is rotated allows theunequal distribution of temperature resulting from the positioning ofheating lamps 52 to be prevented, and in addition, allows the heatdissipation throughout wafer W to become fairly uniform as a result ofthe entire undersurface of wafer W being in contact with turntable 48.Accordingly, the pyrolytic decomposition reaction can occur uniformlythroughout the entire wafer surface, further contributing to improveduniformity of layer thickness and quality. Moreover, in this embodiment,the pressure inside second process chamber 14 is higher than normal airpressure, which also increases the boiling point of the film depositionfluid. As a result, natural evaporation from the surface of the filmdeposition fluid during the pyrolytic decomposition reaction isinhibited, thus yielding a stable pyrolytic decomposition reaction. Oncethe pyrolytic decomposition reaction procedure has ended, wafer W istransported out of second process chamber 14 and the film depositionprocess is completed.

In this manner, by separating the application procedure and thepyrolytic decomposition reaction procedure, a superb copper thin filmmay be obtained having uniform film thickness and quality throughout itssurface in the manner described above; however, in addition to this,since the application process can be performed at temperatures withinthe non-reactive range, residual film deposition fluid may be collectedand reused making it economically advantageous. Furthermore, since thefilm deposition fluid flows in its fluid form, no actual problemsrelated to blockage forming in the supply system develops. In addition,the extremely high speed of film deposition, compared to the MOCVDprocess, is particularly effective in cases where thicker films are usedsuch as during the process of filling holes or trenches.

The first embodiment is described in detail above; however, variousalternative modifications may be performed without deviating from thescope of present invention.

For example, in the above embodiment, nozzle 32 has a structure allowingit to swing; however, as shown in FIG. 4, it may also be moved back andforce in a straight line using direct movement mechanism 80.

Furthermore, the film deposition fluid sputtered from nozzle 32 may beatomized (sprayed). In this case, a number of variations can beconsidered, such as providing a means of atomization whereby nozzle 32itself is a misting nozzle that injects and splatters a film depositionfluid from tiny holes; providing a means of misting whereby a throttle84 is formed inside inert gas injection tube 82 and the negativepressure formed at this throttle 84 is used to suck out the filmdeposition fluid inside supply pipeline 86; or providing a means wherebyfilm deposition fluid is atomized using ultrasonic waves. In cases wherefilm deposition fluid is atomized onto the surface of wafer W, thesurface of the wafer can be effectively moistened so that it becomespossible to reduce the amount of film deposition fluid supplied. Even incases where wafer W is placed on a fixed susceptor without usingturntable 22, it is possible to apply film deposition fluid with uniformfilm thickness and quality by appropriately scanning wafer W with theend of nozzle 32 or inert gas injection pipe 82. It is noted here thatit also becomes possible to perform localized application by injectingfilm deposition fluid without turning wafer W. Namely, the filmthickness in certain localized portions of the surface of wafer W may bechanged, or the deposition of film in areas such as the beveled portionaround the rim of wafer W may even be avoided all together.

Here, another means of preventing film deposition fluid from beingapplied to the beveled portion of wafer W will be described. In thisbeveled portion, the film is unstable, may easily flake off, andincreases the probability that it may be particlized, which is why it ispreferable to not perform film deposition in the beveled portion ofwafer W. Furthermore, when chemical metal polishing (CMP) is performed,it can cause residual dregs to develop and in addition, when a point inthe beveled portion is made the CMP process endpoint, if a film has beenformed, the endpoint can no longer be the same, becoming another reasonwhy film thickness may differ among devices. Since there is no film ofany other material formed at the peak (rim) of the beveled portion, if acopper film is formed here then the copper will spread into the base(Si) of the silicon wafer W increasing the possibility that thecharacteristics of the manufactured semiconductor device will beunstable.

FIG. 6 shows a means of preventing film deposition fluid from adheringto beveled portion Wb of wafer W. This means is structure that is builtinto the film deposition apparatus 10 that was described above in FIG.2, and has the structure whereby a ring-shaped injection trough or aplurality of injection holes 88, which inject inert gas uniformlytowards the outer circumference of wafer W, are formed on the surface ofthe circumference of turntable 22 in first process chamber 12. With thistype of structure, when inert gas is injected from the ring-shapedinjection trough or injection holes 88, the inert gas is blown towardsthe outer rim of the underside of wafer W, and a part of it travelsaround beveled portion Wb reaching the outer rim of the surface of waferW. As a result, film deposition fluid L on the surface of wafer W doesnot reach the beveled portion Wb, and even if it does reach it, it isremoved due to the force of the wind. Of course, the provision of aseparate ring-shaped nozzle (the component drawn with the dotted line inFIG. 6) exclusively for blowing inert gas around wafer W can beconsidered as a means of blowing inert gas to prevent film depositionfluid from adhering to the beveled portion Wb. In addition, coveringmember 92 may be configured, as shown FIG. 7, so as to cover the lowerpart of turntable 22, and inert gas blown into beveled portion Wb ofwafer W through the gas channel which is the gap 94 formed between covercomponent 92 and turntable 22, in the same manner as FIG. 6.

From the viewpoint of preventing film from being deposited on beveledportion Wb, it is also acceptable to spray a gas that inhibits apyrolytic decomposition reaction from occurring on beveled portion Wb insecond process chamber 14. The same structure as that shown in FIG. 6and FIG. 7 may be considered as a means of spraying such gas. Theinventors discovered that when tmvs is sprayed onto the film depositionfluid during pyrolytic decomposition, the pyrolytic decompositionreaction at that spot is inhibited; however, when tmvs is supplied as areaction suppressing gas, since a high density of reaction suppressinggas exists along the rim of the underside of wafer W, beveled portionWb, and the rim of the front side, deposition may be prevented in thoseregions.

Also, variety of forms may be considered for application device 26,which is provided in first process chamber 12, and is not limited to thenozzle (spin coating) or atomized (spray) formats mentioned above. Forexample, application device 126 outlined in FIG. 8 employs a rollerformat. Specifically, this application device 126 comprises a spongeroller pad 100 positioned above turntable 22. Roller pad 100 issupported by supporting member 102 at both ends in a manner such that itis allowed to roll with its rotational axis horizontal. This supportingmember 102 is able to move up and down driven by driving device 104,which is configured on the ceiling of process chamber 12, in a mannerthat facilitates attachment and separation to and from wafer W, which issupported by turntable 22. Supporting member 102 may also be moved backand forth horizontally.

Sputtering pipe 106, which delivers film deposition fluid in order towet roller pad 100, is also attached to supporting member 102. The endof this sputtering pipe 106 is situated above roller pad 100, andhorizontal portion 107, along which are configured a plurality ofsputtering outlets, is horizontally extended along roller pad 100,running along almost its entire length. Consequently, when filmdeposition fluid is poured through the delivery outlets of sputteringpipes 106 and 107 from the supply system, roller pad 100 becomes fairlyevenly wet with film deposition fluid.

With this type of structure, when film deposition fluid is applied towafer W, as film deposition fluid is being sputtered continuously orintermittently, drive device 104 is activated to lower roller pad 100and bring it into contact with wafer W. It is then rolled back and forthover the surface of wafer W. While this is occurring, turntable 22begins to rotate at a relatively slow speed and film deposition fluid isapplied to the portion that is in contact with roller pad 100. Therotation of turntable 22 and the back and forth movement of roller pad100 are appropriately adjusted so that film deposition fluid may beapplied uniformly to the entire surface of wafer W. In this case, sinceonly those portions that come into contact with roller pad 100 have beenapplied, there is little film deposition fluid wasted and thus effectiveat dramatically reducing the amount of fluid spillage.

FIG. 9 shows another alternative form of the application device 126 thatis shown in FIG. 8. Application device 126 in FIG. 9 is different fromthat shown in FIG. 8 in that it further comprises mask 108 to preventapplication to the no-application areas, namely the outer extremities(beveled portion) of wafer W. This mask 106 is supported within firstchamber 12 using support shaft 110. Support shaft 110 is configured suchthat it is able to rotate and also move up and down. Consequently, byactivating drive device 112 of support shaft 110, mask 108 can be swunginto place over wafer W on turntable 22, then lowered to adjoin theouter extremities of wafer W making it possible to perform masking ofthose portions. Roller pad 100 is thus not able to come into contactwith the portions that are covered by this mask 108; thereforepreventing application to those portions. It is understood that themechanism for moving mask 108 is not limited to the configuration shownin the Figure.

In this manner of application device 126, the same results are obtainedif, instead of roller pad 100, a supple brush is used. Alternatively itis possible to use as a roller application device a chemical metalpolishing (CMP) device (not shown in the Figures), which is a devicethat wets the pad of its platen with a polishing slurry, brings it intocontact with the surface of the wafer, and moves them relative to eachother, if instead of slurry film deposition fluid is supplied for thepad of its platen. In current semiconductor manufacturing facilities,where multi-stage processing with a plurality of CMP devices is widelyused, one of the stages may be effectively used as an applicationdevice.

As shown in FIG. 10, an immersion-type device may also be used asanother, alternative application device. Application device 226 in FIG.10 is comprised of fluid tank 200, which holds the film deposition fluidthat is supplied from the supply system 28. Wafer W is lowered intofluid tank 200 from above, which means that turntable 22, unlike in theabove embodiment, is configured facing down in order to soak the surfaceof wafer W in the film deposition fluid of fluid tank 200, and hangsdown from the ceiling of process chamber 12 in a manner such that it isable to move up and down. Ring-shaped clamp 202 is provided on thisturntable 22 so that the rim of wafer W may be sandwiched in betweenclamp 202 and the holding surface of turntable 22. If the adhesivenessof clamp 202 and turntable 22 to wafer W is high enough, then the filmdeposition fluid is not able to seep into the portion that is in contactso that the application of film deposition fluid to the beveled portionand the undersurface of wafer W may be prevented. It is noted here thatwafer W may be immersed in the film deposition fluid by simply beinglowered; however, since the application or adhesion may not be veryeffective, it is preferable that turntable 22 be rotated. In addition,it is possible to improve the uniformity of application and filling-incharacteristics in cases where a wafer support means that does notrotate is used instead of turntable 22, by causing the wafer supportmeans to vibrate and/or the film deposition fluid to vibrate.

The application characteristics of the film deposition fluid to wafer W,such as adhesion or penetration, largely depend on the viscosity of thefilm deposition fluid and the base material of the under layer; however,in cases where this immersion-type application device 226 is used, it ispossible to effectively apply film deposition fluid to the top of waferW without regard to the dependent factors such as viscosity.Furthermore, after wafer W is pulled back up, since surplus filmdeposition fluid returns to fluid tank 200, the amount of filmdeposition fluid used may be reduced.

The heating means used for causing a pyrolytic decomposition reaction tooccur in second chamber 14 is not limited to heating lamps 52. Forexample, a resistance heater, an induction-heating device, or an oilheater may be integrated into the turntable that acts as a wafer supportmeans or into the susceptor.

In the first embodiment and the alternatives described above, theapplication procedure is performed in one of the two process chambers 12and 14, and the pyrolytic decomposition reaction procedure is performedin the other. Nonetheless, it is also possible to perform both of theseprocedures sequentially in just one chamber. FIGS. 11 and 12 areschematic diagrams of the second embodiment of a film depositionapparatus 300 according to the present invention, in which there is onlyone process chamber.

In FIGS. 11 and 12, reference numeral 302 denotes the process chamber,and on its ceiling there are configured a plurality of, for example,halogen heating lamps 52. Inside process chamber 302, there areconfigured turntable 22, which is similar to the turntable in the firstembodiment, and nozzle 32, which is similar to the direct movement-typenozzle that injects film deposition fluid as shown in FIG. 4. Along theperiphery of turntable 22, ring-shaped wafer support 304 is configuredhaving the same axis as turntable 22. This wafer support 304 is moved upand down by means of lift mechanism 306. On wafer support 304, there isformed concave region 308, which has a diameter that is slightly largerthan the diameter of wafer W, and into this concave region 308, wafer Wis fitted so as to be held in place. Lift mechanism 306 is configured ina manner such that it may be rotated by a drive motor (not shown in theFigures). Since lift mechanism 306 and wafer support 304 are formed as asingle mass, if lift mechanism 306 is rotated, then wafer support 304 isalso rotated. The other structural components are similar to those shownin FIG. 2; as such, they are assigned the same reference numerals andtheir descriptions are omitted here.

With this type of configuration, to begin with, wafer W, which has beencarried into process chamber 302 in the same manner as with the firstembodiment, is placed on turntable 22 and locked. Next, as turntable 22is being rotated, nozzle 32 and the film deposition fluid supply systemare activated to apply film deposition fluid to the surface of wafer W.At this point, wafer support 304 is positioned by lift mechanism 306 tobe lower than the upper surface of turntable 22 (see FIG. 11).

Once the application of film deposition is completed, wafer W isreleased from being locked onto turntable 22 and wafer support 304 israised up by lift mechanism 306. As a result, as shown in FIG. 12, waferW is transferred onto the concave portion of wafer support 304,separated from turntable 22, and positioned at a location directly belowheating lamps 52. Heating lamps 52 are then illuminated and wafer W isheated to cause the pyrolytic decomposition reaction to occur throughoutthe film deposition fluid, thus effectively forming a copper film onwafer W. While this is occurring, lift mechanism 306 and wafer support304, and accordingly wafer W on top of wafer support 304, are allrotated to even out the temperature distribution of wafer W, whichcontributes to the uniformity of the film thickness and quality of thesurface.

With the embodiment shown in FIGS. 11 and 12, wafer W is transferredfrom the application area to the heating area by means of lift mechanism306 and wafer support 304 (transfer means); however, if there is asufficient amount of heat radiating from heating lamps 52, it may alsobe feasible to also lock in wafer W and not move it from turntable 22during the pyrolytic decomposition reaction.

As it is conceptually shown in FIG. 13, film deposition apparatus 400,which is a similar single chamber-type film deposition apparatus capableof performing the two procedures inside a single chamber, has anintegrated wafer support means 404 such as a susceptor, which in turncomprises an integrated heating means 402 such as a resistance heater.This wafer support means 404 employs a configuration whereby wafer W maybe lifted using lift pin 406, so that when wafer W has been lifted bylift pin 406, application may be performed using, for example, aroller-type application device 126. Then the pyrolytic decompositionreaction may be performed once wafer W is lowered and supported by wafersupport means 404.

In the above, the preferred embodiments of the present invention aredescribed in detail; however, it is understood that the presentinvention is not limited to the various examples mentioned above. Forexample, in the above examples, film deposition fluid is fluidcontaining a mixture of a copper diketonate such as (hfac)Cu⁺¹(tmvs) andor an aliphatic saturated hydrocarbon such as heptadecane; however, itis also feasible to have the organic metal be another copper diketonatesuch as (hfac)Cu⁺¹(teovs), or any other suitable organic metal. Inaddition, as the organic solvent for the copper diketonate, anotheraliphatic saturated hydrocarbon such as pentadecane, hexadecane, oroctadecane may be used, and for organic metals besides copperdiketonate, any other appropriate solvent may be used. Furthermore, asdescribed above, the film deposition fluid may include only the organicmetal.

Industrial Applicability

As described above, according to the present invention, the applicationprocedure of applying organometallic fluid (film deposition fluid) to awafer, and the pyrolytic decomposition procedure of causing a pyrolyticdecomposition reaction of the organic metal in the applied filmdeposition fluid are performed separately so that film deposition fluidmay be applied having uniform film thickness and quality within thewafer. Also, by adding heat in a later step, a thin film having superiorfilm thickness and quality throughout its entirety may be formed.

When the present invention is put to use in semiconductor devicemanufacturing, since thin films having superior film thickness andquality within the wafer may be effectively formed, it is possible toproduce a high quality semiconductor device.

Furthermore, with the present invention, film deposition fluid is usedin its liquid form; therefore, the efficiency of film deposition is farmore superior than CVD processes, and particularly more effective forimplantation processes. Still further, it is effective in that problemssuch as pipelines in the film deposition fluid supply system becomingclogged are virtually eliminated.

1. A film deposition method comprising: a first step of preparing afluid that has organic metal as a main component which precipitates afilm deposition material using pyrolytic decomposition, wherein thefluid comprises an aliphatic saturated hydrocarbon solvent and theorganic metal is a copper diketonate; a second step of applying thefluid onto a to-be-processed body at a temperature within thenon-reactive range of the organic metal; and a third step of heating theto-be-processed body to a second temperature, and causing a pyrolyticdecomposition reaction of the organic metal throughout the fluid that isapplied onto the to-be-processed body to occur to form a copper film onthe to-be-processed body.
 2. The film deposition method in claim 1,wherein the to-be-processed body is a semiconductor wafer.
 3. A filmdeposition method comprising: a first step of preparing a fluid that hasorganic metal as a main component which precipitates a film depositionmaterial using pyrolytic decomposition, wherein the organic metal isselected from the group consisting of (hfac)Cu(tmvs) and (hfac)Cu(teovs)and the fluid further comprises an aliphatic saturated hydrocarbonsolvent; a second step of applying the fluid onto a to-be-processed bodyat a temperature within the non-reactive range of the organic metal; anda third step of heating the to-be-processed body to a secondtemperature, and causing a pyrolytic decomposition reaction of theorganic metal throughout the fluid that is applied onto theto-be-processed body to occur to form a copper film on theto-be-processed body.
 4. The film deposition method in claim 3, whereinthe to-be-processed body is a semiconductor wafer.
 5. A film depositionmethod comprising: a first step of preparing a fluid that has organicmetal as a main component which precipitates a film deposition materialusing pyrolytic decomposition, wherein the fluid further comprises analiphatic saturated hydrocarbon solvent; a second step of applying thefluid onto a to-be-processed body at a temperature within thenon-reactive range of the organic metal; and a third step of heating theto-be-processed body to a second temperature, and causing a pyrolyticdecomposition reaction of the organic metal throughout the fluid that isapplied onto the to-be-processed body to occur to form a film on theto-be-processed body.
 6. The film deposition method in claim 5, whereinthe organic metal is a copper diketonate.
 7. The film deposition methodin claim 6, wherein the copper diketonate is selected from the groupconsisting of (hfac)Cu(tmvs) and (hfac)Cu(teovs).
 8. The film depositionmethod in claim 7, wherein copper is deposited as a film.
 9. The filmdeposition method in claim 8, wherein the to-be-processed body is asemiconductor wafer.